1. Field of the Invention
The present invention relates to an object, a method, or a manufacturing method. In addition, the present invention relates to a process, a machine, manufacture, or a composition of matter. In particular, the present invention relates to, for example, a power storage device, a secondary battery, a driving method thereof, or a fabrication method thereof. In particular, the present invention relates to, for example, an electrochemical device and a driving method of an electrochemical device. In addition, the present invention relates to, for example, a system having a function of reducing the degree of degradation of an electrochemical device.
Note that an electrochemical device in this specification generally means a device that utilizes an electrochemical phenomenon, specifically, a battery or the like.
2. Description of the Related Art
A lithium-ion secondary battery, which is one of electrochemical devices, is used in a variety of applications including a power source of a mobile phone, a fixed power source of a residential power storage system, power storage equipment of a power generation facility, such as a solar cell, and the like. Characteristics such as high energy density, excellent cycle characteristics, safety under various operating environments, and long-term reliability are necessary for the lithium-ion secondary battery.
In addition, the lithium-ion secondary battery includes at least a positive electrode, a negative electrode, and an electrolytic solution (Patent Document 1).